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Auto decompression spring

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Im replacing the spring and plunger that relates to the auto decompression system under the cam. The original spring disappeared somehow, which gives me the impression that it was loose inside the channel. This new spring is extremely tight....goes in eventually, but tight, and it doesn't seem to offer any springyness to the plunger. Is this normal? The plunger is free to move and is flush with the top of its hole.

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No, that doesn't seem right. The spring to hole wall clearance should not be interference fit. There should be enough clearance between the spring and hole wall for freedom of movement(compression) of the spring.

Sounds like you got the wrong or a bad spring.

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Just verified the part number and it seems to be correct. 14106-MN1-670

The spring goes in, but you definitely have to press it and once its all together it doesn't provide any springyness. Will the system work with only the plunger in place without the spring? I take that back slightly. I am now able to get a little spring out of it. I compresses just below the hole surface and them comes back flush. Is that normal? The shop manual pick looks like it shows the plunger actually protruding some.

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Just verified the part number and it seems to be correct. 14106-MN1-670

The spring goes in, but you definitely have to press it and once its all together it doesn't provide any springyness. I take that back slightly. I am now able to get a little spring out of it. It compresses just below the hole surface and then comes back flush. Is that normal?

>>>>>>>>>Will the system work with only the plunger in place without the spring? <<<<<<<<<<

No.

>>>>>>>>>>The shop manual pick looks like it shows the plunger actually protruding some.<<<<<<<<<<

The system wouldn't work if the plunger remained flush with it's hole, so yes it should be able to protrude, to make and stay in contact with the auto decomp cam as it rotates. That's where the spring comes into play.

I think I would do whatever I needed to to make sure the spring is compressing and decompressing freely in the hole and also that the plunger itself isn't sticking against the sides of the hole. Look for burrs, nicks, flat spots on the plunger, a sharp edge to the hole rim itself, wear to the hole wall.

You might lightly file the springs outside coil surface. May take only very little to free it up. It may be the right part number but no telling who the manufacturer of it is and how closely its spec. tolerances were held to.

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After looking over the entire world I finally found someone who carried a spring that I thought might work. I had to cut it down to size, but one reassembled the bike started with the first kick and ran good and strong. Thanks for the help.

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